What is Earthing and why is it necessary?
Earthing is the grounding or fastening electrical installations to earth. In electricity supply systems, an earthing system defines the electrical potential of the conductors relative to that of the Earth's conductive surface.
Installation and maintenance of an effective low resistance earthing system is essential due to the following-
- Efficiently dissipate heavy fault currents and electrical surges, both in magnitude and duration, to protect equipment being damaged so as to minimize down time, service interruption and replacement cost.
- Provide a stable reference for electrical and RF circuits at the installation to minimize noise during normal operation.
- Protection of personnel who work within the area from dangerous electric shock caused due to step potential or touch potential.
Characteristics of good Earthing system
- Excellent electrical conductivity
- Low resistance and electrical impedance
- Conductors of sufficient dimensions capable of withstanding high fault currents with no evidence of fusing o mechanical deterioration.
- Lower earth resistance ensures that energy is dissipated into the ground in the safest possible manner.
- Lower the earth circuit impedance, the more likely that high frequency lightning impulses will flow through the ground electrode path, in preference to any other path.
- High corrosion resistance
- The choice of the material for grounding conductors, electrodes and connections is vital as most of the grounding system will be buried in the earth mass for many years. High hot dipped galvanised electrodes should be used to for this purpose.
- Mechanically robust and reliable.
- Should be maintenance free.
Earth Enhancement material (SABO-EREC)
SABO-EREC is a superior conductive material that improves earthing effectiveness, especially in areas of poor conductivity (rocky ground, areas of moisture variation, sandy soils etc.). NABL Lab tested 0.039 Ohm-m resistivity. It improves conductivity of the earth electrode and ground contact area. It has following characteristics:
- high conductivity, improves earth absorbing power and humidity retention capability.
- non-corrosive in nature having low water solubility but highly hygroscopic.
- suitable for installation in dry form or in a slurry form.
- depends on the continuous presence of water to maintain its conductivity.
- permanent & maintenance free and in its set form, maintains constant earth resistance with time.
- thermally stable between -100 C to +600 C ambient temperatures.
- does not require periodic charging treatment nor replacement and maintenance.
- suitable for any kind of electrode and all kinds of soils of different resistivity.
- does not pollute the soil or local water table and meets environmental friendly requirements for landfill.
- non explosive.
- does not cause burns, irritation to eye, skin etc.
SABO-EREC can be used for all types of earthing Pipe, plate, electrode, etc.
Available in 10Kg moisture proof and sealed bags / buckets.
Required SABO-EREC in 2m deep earth pit with 100-125mm dia hole - 20 kg
Required SABO-EREC in 3m deep earth pit with 100-125mm dia hole - 30 kg
Should be mixed with minimum 6 times volume of water thoroughly and then poured inside earth pit. It takes 2 to 4 weeks time in getting fully set.
Once set will give lowest possible earth resistance value and maintain it round the year.